


A Cathedral Defiled

by nevereatdirt



Series: Omega Sylvain Week [1]
Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Alpha Dimitri Alexandre Blaiddyd, Alpha/Beta/Omega Dynamics, Bottom Sylvain Jose Gautier, Knotting, M/M, Mating Cycles/In Heat, Mild Blood, Mildly Dubious Consent, Omega Sylvain Jose Gautier, Omega Sylvain Week, Top Dimitri Alexandre Blaiddyd, there's some scratching nothing explicitly described
Language: English
Status: Completed
Published: 2020-05-03
Updated: 2020-05-03
Packaged: 2021-03-02 01:27:29
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,803
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23976715
Author URL: https://archiveofourown.org/users/nevereatdirt/pseuds/nevereatdirt
Summary: He wasn’t supposed to be here this long.He’d planned for the journey there and back. He’d planned for a few skirmishes and many a tryst. But he hadn’t planned foreveryoneto be at the monastery. It was a promise they’d made five years ago. One he hardly took seriously back then. Fighting alongside his entire former class to take down a group of bandits feltfreeingthough and he didn’t regret staying with them to help Dimitri, but now… his unplanned stop had led to problems.
Relationships: Dimitri Alexandre Blaiddyd/Sylvain Jose Gautier
Series: Omega Sylvain Week [1]
Series URL: https://archiveofourown.org/series/1728730
Comments: 2
Kudos: 72
Collections: Omega Sylvain Week





	A Cathedral Defiled

**Author's Note:**

> written for omega sylvain week, day 1: heat

He wasn’t supposed to be here this long.

He’d planned for the journey there and back. He’d planned for a few skirmishes and many a tryst. But he hadn’t planned for _everyone_ to be at the monastery. It was a promise they’d made five years ago. One he hardly took seriously back then. Fighting alongside his entire former class to take down a group of bandits felt _freeing_ though and he didn’t regret staying with them to help Dimitri, but now… his unplanned stop had led to problems.

He could feel the changes in his body once he’d run low on his suppressants and started taking half doses. He could even smell his own scent hanging more thickly in the air around him, and he knew that all of his former classmates could too. He’d been running dangerously low by their journey to Ailell but now they were on the brink of the greatest battle they’d seen yet. Their twisted class reunion at Grondor Field.

The last terrible leg of his unpreparedness was upon him now, though. He’d taken the last half of a dose two days ago and his body was starting to _burn_ in a way he hadn’t felt since he was thirteen and had his first heat. It was so bad that opening the window in his room didn’t help and he was just delirious enough to think a walk was a good idea. The Great Tree Moon usually meant for cooler nights… at least in Faerghus. But here at the monastery it felt stifling. Or maybe it was the armor?

It had to be. He walked into the cathedral and sat in a pew, stripping his armor and setting it aside carefully. With the chestplate off he could at least breathe easier but the heat was still bearing down on him, and now he couldn’t shake the feeling that there were eyes on him.

Part of him knew someone might be here with him. It was a massive public space, after all but the fact he could _smell_ an alpha had him on edge. How many alphas could be there at all? Easily half of his classmates, countless knights and refugees now, Seteth, Catherine… too many for comfort. Even through the thick fog of heat in his mind he knew that this could be dangerous. Without any armor on, or the presence of mind to put it _back_ on, he rose and surveyed the open room.

Rubble marred the back half of the cathedral yet, and anyone could have been hiding there. Was that a growl? He wasn’t sure but the scent of the alpha in this open space was beginning to overpower any sense of logic he had left. Who _was_ this though? It was familiar. Crisp winds. The sharp, dangerous tinge of _copper_ and a strange earthiness under it all.

Oh no.

The growling grew louder and suddenly the scent was overwhelming. The Mad King himself. His breath caught in his throat and not even the Goddess herself could have stopped the pathetic _whine_ that came from him when he felt the looming presence behind him. He had to swallow thickly before he could speak, his voice more raw than he could have predicted. “Hey Dima.” He cursed himself some. Part of him wanted to just bend over and get it all over with, and part of him wanted to run from that tinge of copper in his scent.

“Sylvain.” Dimitri’s voice was dark. He’d grown used to that darkness in his voice but there was the subtle _growl_ alongside that darkness now that had his knees trembling. “What are you doing here?”

An excellent question, really. He tried to wrack his brain for the answer but all he could think about was the _growling_ behind him. “Oh you know. Felt like a walk and made my way here.” He felt frozen in place, especially as Dimitri pressed against him some. Had he always been so big? At the academy he’d been so _slight_ and he hardly looked as strong as he truly was. But now… he could feel his strength even in the way they brushed against each other.

“You shouldn’t be here in your… condition.” The strain in his voice made Sylvain wonder just how long Dimitri had been keyed into his scent.

“My condition?” Was he really going to be daring? He was. On shaky legs he turned around and looked up to meet Dimitri’s dangerous, icy gaze. “What does it have to do with where I am?”

His cheekiness was met with another low growl as Dimitri’s eye narrowed. “You never know who could take advantage of you in a place like this.”

Sylvain decided in the moment to be a little more daring. He was captivated now by the taller man and he knew there was no escape in his heat-addled mind. With that bit of courage he pressed against his chest. “I think I know who.” His voice was quiet and he couldn’t help the whine that left him. He knew just what he needed and it was now or never.

He could _feel_ the growl in Dimitri’s chest and that along with the gush of slick from him left him a needy mess. “And just who do you think?” A hand reached up and the cold metal of his gauntlet rested lightly at Sylvain’s throat, the sharp tips of its claws almost grazing against his skin. A feather light touch. More a threat than a real danger… he hoped.

“Well,” a nervous laugh escaped him and he shuddered some, “you?” He gave a sheepish grin and couldn’t help shaking.

His eye narrowed again and he put just a slight pressure on Sylvain’s throat, the tips of his claws pricking his skin. “You _who_?”

His breath hitched and he couldn’t help but arch his back some. “You, A-Alpha?” The pressure let off his throat and he took a few deep breaths, waiting for the other to move as the growls reverberated in the empty cathedral.

“Good boy.” His voice was even lower now. Darker and dripping with something Sylvain would only describe as _lust_. Had he been thrown into rut? “Strip before I tear your clothes off.”

Even in the thrall of heat and the scent of an alpha on the edge of rut he couldn’t help his cheeky grin. “What if I want you to, Alpha?” His voice was breather than it had been and the tinge of _need_ was obvious even to him.

The grip on his throat tightened again and the tips of his gauntlet dug into his skin as a low growl sounded in Dimitri’s throat. “Don’t get smart.” The grip let loose again and Sylvain was pushed back onto the floor.

The wind was knocked from him and he lay there stunned as the Mad King hovered above him, his piercing gaze dark as he looked him over. Assessing him somehow. As he caught his breath, Sylvain watched him with a touch of panic tinging his now overwhelming arousal. “I’m sorry, Alpha.” The speed of his words amazed him. Never in a thousand years would he have thought this possible. Sweet, awkward Dimitri was here above him now. A dangerous, dark beast who was ready to take what they both knew was his.

Dimitri growled again and worked carelessly at tearing Sylvain’s clothes from him. The scraps landed all around them, leaning Sylvain laying helpless and naked beneath him. Dimitri studied him carefully and let out another low growl at the slick pooling beneath the now prone omega. “Good.” The claws of his gauntlets dragged down his thighs, leaving angry red scratches in their wake. He looked him over again before leaning down and lapping at his slick with another low growl.

The sudden feeling of his tongue sent a surge of pleasure through Sylvain, forcing a keen from him before he could cover his mouth. He’d never been touched during a heat before, especially not one so intense as this. It felt like his body had been set aflame again by such a small, simple act. If everything he’d done before was just sex then this had to be something else, something _more_ starting from such a simple touch. 

He felt electricity run through him with each hungry swipe of his Alpha’s tongue. _His Alpha?_ When had he started to think that? It had been mere moments since he’d even called his childhood friend _Alpha_ at all and now… his heat had completely taken over. He moaned and keened behind his hand before he felt a strong grip pull it from his mouth and a low voice drawing his attention. “Be good. I want to hear you.”

Dimitri stared up at him from between his legs, slick smeared over his face and his hair disheveled. When Sylvain found his voice it was breathy and shaking, his words almost coming out on instinct. “I’ll be good Alpha.” Another whine left him, drawing a rumbling growl from Dimitri.

Without another word, Dimitri flipped him over onto all fours and settled behind him. Sylvain could hear the rustling of the other’s cloaks as he moved and the sound of clasps and snaps before he felt pressure against his slick entrance. A needy moan escaped him and he tried to press back, only to be greeted by strong hands and sharp claws holding his hips tight. “Be _good._ ”

He moaned and nodded, trembling some as his overheated chest pressed against the cool stone flooring. He gripped at the ground as best as he could, letting out another moan as Dimitri pressed his thick cock into him. Feeling the stretch around him was almost too much at once, his vision going white for a moment from the familiar mix of pain and pleasure. How long had it been since he’d let anyone take him? _Too long_ , the now thoroughly heat addled omega thought to himself.

Why had he denied this part of himself for so long? Every thrust of the other’s cock drove him further into bliss, even the sharp drag of his claws raking against his skin made him moan louder and louder. When the other stilled, though, he let out a needy whine and looked over his shoulder at him. “Alpha… _please_.” It wasn’t like him to beg. At any other time he’d be kicking himself but now… his body was a desperate thrum of want and sex.

His words drew another low, rumbling growl that echoed in the cathedral from Dimitri before he started to fuck into him roughly. Teeth met his neck and a brief moment of panic flashed in his system. Dimitri was practically feral right now. A beast. A beast in rut mounting his _bitch_ . Sylvain moaned loudly when that thought flashed through his mind. The rough, angry thrusts of his Alpha’s cock left him desperate for more, more, _more_.

A still armored chest pressed against his back as Dimitri bit over his neck and fucked into him even harder. But he wanted, _needed_ , more from him. “Alpha more _please_ I need more!”

Dimitri growled loudly and bit harder at his neck, raking his claws lightly down his sides. “So desperate to be knotted and filled aren’t you, greedy Omega?”

“ _Yes._ Please just _please_ knot me! _Breed_ me Alpha I need your cum! I need your _knot_!” The words spilled from his mouth in a haze, his eyes rolling back with the rough treatment and slick gushing out around his cock.

“Not yet.” His voice had grown hoarse and low, his desperation clear even in just two words. But his hips stilled, pulling out before flipping Sylvain onto his back again. “I want to watch you.”

He let out a high whine and spread his legs, showing off his slick, gaping hole. “Alpha _please_.” Tears stung his eyes and heat coursed through his body again, the ache of being empty leaving him dizzy with need.

He was left waiting in near agony as Dimitri stripped off his furs and armor. The flush of his need was apparent over his pale skin and Sylvain couldn’t help the needy whine at seeing his thick cock standing fully erect and throbbing. In a swift move, he was back between Sylvain’s legs and snapping his cock back into him roughly.

They both let out a chorus of moans, the sound of growls and whines reverberating in the cathedral creating a symphony around them. As Dimitri bit over his neck more, Sylvain wrapped his arms around his shoulders and his legs around his hips, clinging and pulling desperately for more from his Alpha. His body needed _something_ that it wasn’t getting. Each bite was just a teasing reminder. Each thrust an agonizing push towards an edge it felt he would never reach.

Though with one sharp bite and the feel of his Alpha’s knot _swelling_ against him, he knew what it was. With nearly all words out of his mind, the only thing he could shout was simple. “Alpha! Mark please please!” It earned a terrifying snarl and a sharp, piercing bite on his neck as Dimitri clamped down hard and snapped his thick knot into him.

The feeling of the stretch sent him over the edge, forcing him to cum over their stomachs as he was filled with the hot, thick cum he’d so desperately craved. He moaned and rocked back against his thick knot, drooling as he came over himself again.

With cum filling him and his Alpha clamped down on his throat, Sylvain could feel some of the heat leaving him though the fog of need still hung over him. His stomach began to swell as Dimitri came more and his mind seemed to only focus on one thing. The word spilled from him before his brain could process anything but the feeling of _fullness_. “Pup?” He whined and rocked back against him as he came again, keeping his hold on him tight.

Dimitri moaned as he let off his neck and lapped at the mark he’d left, tracing over him slowly as he continued to cum. “Yes… pup.” He growled softly and kissed over his neck. “Our pup.”

Sylvain relaxed a little, his mind still foggy and fucked out but the feeling of his heat finally passing if even just for a moment. A smile graced his lips as he held Dimitri tight still, hiding his face. “Thank you.” He panted and held him tight, furrowing his brow some as he felt the other tense. “Hey? What’s wrong?”

All thoughts of the feral beast that had fucked him open, _bred_ him, had left his fuck drunk head. Now what was left was worry for the crybaby he’d known as a boy. Dimitri’s words came soft and low. “Are… you okay?”

Those were the first words of concern he’d heard from his friend in five years, and they left an ache deep in his heart. Part of that boy he knew was still inside this so called beast; he could see that clearer than he would have an hour ago. “I’m okay, Dimitri.” He kept his voice soft but laughed a little. “More than okay. That was _wild_.”

That earned a sigh as Dimitri moved to lock their gazes, looking him over with a solemn expression. “I… you didn’t…”

He rolled his eyes and cups his cheeks. He could feel Dimitri tense at his touch and gave him a grin. “Hey now. Even burning up in heat I would say yes to you.” He tilted his head some. “We went through a lot together growing up.” He watched him avert his gaze and pulled him close to kiss him quickly. “Trust me. And trust yourself with this, okay?” He traced his thumbs over his cheeks and felt the other relax on top of him, pressing on his cum swollen stomach.

Dimitri pulled them onto their sides and moved a hand to rest against his stomach. “What about this?”

Sylvain relaxed and let out a purr, shaking his head. “We’ll figure that out. I might just be okay for now.” He closed his eyes and took in the feeling of calm in his mind and the scent of crisp air. Earthiness. Polished leather. He couldn’t smell the copper anymore, even though he knew from all the scratches that he should. No… for now he wasn’t with the Mad King. A feral beast. A man back from the dead. No. Now he was just with Dimitri. Dima. One of his best friends, and now… the man he was marked by.

It all came from the heat. It was all so stifling, but laying there in his arms, he had a feeling for the first time in a while, that he could at least pretend that things were okay.


End file.
